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MORGAN IN NORTH DAKOTA ASKS:
My whole family has sensitive skin, and we seem to be getting progressively more itchy year to year. Our dermatologist prescribes creams but doesn’t address the causes of our sensitivity and rashes. I’ve been wondering, Is eczema worsened by air pollution?
MOM DETECTIVE ANSWERS:
Hello, fellow itchy human! I’m so glad you reached out. I too have been dealing with eczema on and off since I was a kid. My dermatologist calls mine atopic dermatitis (AD)—and there are other types too. My older daughter also suffers from it. Did you know parents with eczema are more likely to have kids with it? Sigh. We all keep a lot of good company: AD is said to affect up to 1 in 5 children and 1 in 10 adults worldwide.
For readers who are new to the topic, these are the (very) basics: Eczema is an inflammatory skin condition that causes dry and itchy patches all over the bodies of people with underlying skin barrier defects. These itchy spots flare, or create a heightened immune response, when in contact with irritants and allergens. There are some specific risk factors, like kids are more likely to get it than adults; same goes for people who have asthma and food allergies. Dermatologists generally focus on managing symptoms because there isn’t a cure.
Basic causes of eczema
Like you, I have noticed a general lack of interest in cause—as well as prevention—by my doctors over the years. It’s frustrating. I looked into causes of eczema to educate myself. They’re broad and each person has unique triggers. Still, the culprits include all or some of the following:
Irritants: Soaps and detergents, fragrance (this is a huge one for me, especially in laundry detergent residue on sheets and clothing), and even rough fabrics.
Allergens: Pet dander, dust mites, and some foods.
Weather: When it’s cold and dry, things can be rashier. Ditto hot, sunny, and sweaty summer days (soooo itchy behind the knees where skin touches!).
Hormone fluctuations: Skin sensitivity can worsen in conjunction with monthly hormonal changes plus during pregnancy; stress hormones can also increase inflammation.
Air pollution and atopic dermatitis
You asked if air pollution belongs on this long list of eczema triggers, and the answer is a resounding yes. Both indoor and outdoor air pollution can and do impact sensitive skin. A 2023 comprehensive overview of various skin-related studies and literature states, “The effects of air pollution on AD have been less studied compared to their impact on respiratory and cardiovascular diseases, but some of the underlying pathologic mechanisms, such as triggering inflammatory responses, are similar.”
The review details a number of things that might interest you, Morgan, including that air pollution from a California wildfire was associated with “increased clinic visit rates for itch.” It covers exposure to diesel exhaust particles, children’s exposure to indoor volatile organic compounds (VOCs), and also a study of maternal exposure to VOCs and risk for developing AD in the future. The overview concludes that “the scientific literature evaluated … found evidence in support of an association between air pollution exposure and atopic dermatitis.”
Wildfires are on the rise, so I want to zero in on wildfire smoke and eczema. We know the resulting smoke can travel far distances, so it’s likely going to affect a lot of people’s skin. While there’s solid public health information available on how to minimize exposure to breathing air pollutants during wildfires, reducing risks for skin flares isn’t—yet!—part of standard public conversation. This needs to change. It turns out that protecting skin from air pollution from wildfire smoke is similar to protecting your lungs. Precautions on smoky days include filtering indoor air, wearing clothing that covers your skin, and staying indoors when possible. Filtering indoor air will also protect from other air pollutants—and so will not having things in your house that are known to trigger eczema in the first place, like fragranced products, including cleaners and even candles. Creating a mostly fragrance-free home can go a long way for eczema sufferers.
Managing symptoms
Chances are, if you have eczema, you’re already pretty adept at managing your symptoms. When I was younger, I used the steroid creams my doctor prescribed. But when I was trying to get pregnant years ago, I began to question the creams. They were effective, but some of them weren’t considered safe for use during pregnancy—depending on the steroid and duration of use. How could they be safe for me even when not pregnant? My doctor said it was a dose thing, and I decided to only use it when absolutely necessary from then on. I became more interested in preventing flares, in an effort to minimize using steroids to manage symptoms.
To prevent flares, I had to discover what my triggers are. According to the American Academy of Dermatology Association, more than 15,000 substances can cause an allergic skin reaction! I “patch tested” for what was causing mine. This is when small amounts of chemical allergens are placed on a patient’s back and left there (with a lot of patches/tape!) for a set period, then removed and “read” to see what’s causing allergic reactions. Some doctors debate the credibility of patch testing. It can create false positives, among other things. But it changed my life—and my daughter’s too. I was able to pinpoint my very reactive triggers and knowing what to avoid in daily life means I am, after decades, mostly eczema-free. My kid has vastly improved too.
A word on petroleum jelly
When symptoms are triggered, in addition to steroids, doctors frequently suggest showering, then creating a “barrier” with petroleum jelly, a.k.a. petrolatum, on damp skin to “lock in” moisture—but only the kind with no added ingredients, including fragrance. A colleague asked me the other day about this practice, since we do a fair amount of work here at Moms on petrochemical pollution. She wanted to know if it was safe to slather something called petroleum on her body. It’s a fair question.
I turn to various sources when I’m concerned about the safety of cosmetic ingredients, including the Campaign for Safe Cosmetics and the Environmental Working Group’s Skin Deep database. The former says it is a by-product of petroleum refining, and when properly refined, it has no known health concerns. “However, with an incomplete refining history, petrolatum could potentially be contaminated with polycyclic aromatic hydrocarbons, or PAHs… There is no way to confirm proper refinement unless a complete refining history is provided.” PAHs, they go on to explain, are considered by the National Toxicology Program to contain reasonably anticipated carcinogens. EWG’s Skin Deep database mostly rates petrolatum as relatively low hazard, depending on its use in products.
Still, there are people who prefer not to use petroleum-derived ingredients—especially to soothe skin itching from fossil fuel-related air pollution! There are other ways of locking in moisture and creating a barrier than using an oil-based ointment, says the National Eczema Association. As with all things eczema, no matter the cause, trial and error will lead to what works best for you.